Method and apparatus for preparing artificial materials



J. M. -ALI BERT METHOD AND APPARATUS FOR PREPARING ARTIFICIALMATER'IALsSept. 22, 193

Filed May 5, 1935 'ATI'ORNEY Patented Sept. 22, 1936 V METHOD ANDAPPARATUS FOR PREPARING ARTIFICIAL MATERIALS Jean Marie Alibert, Lyon,France, assignor to Du Pont Rayon Company, New York, N. Y., acorporation of Delaware Application May 3, 1933, Serial No. 669,103 I InFrance June 3, 1932' 7 Claims. (01. 18-8) This invention relates to themanufacture of on which the thread was collected or of the deartificialstraws, tapes, bands, ribbons, horsevice conveying the finishedmaterial. hair and the like, at a rapid rate and without Recently, therehas been devised a process of the usual degradation of the material.More manufacturing. materials of the type hereinparticularly, thisinvention relates to a method before mentioned, whereby only thefilaments on 5 and apparatus for producing materials of the the exteriorof the material were united or glued type mentioned under suchconditions that no together. This was secured bypassing a band or unduestretch will be imparted thereto. bundle of filaments or threads at arelatively high Prior to the instant invention various procspeed incontact with'a solvent or swelling agent 10 esses had been devised andused for the manufacin such a manner that'the latter could not pene- 10ture of artificial straws, tapes, bands, ribbons, trate and cause thefilaments on the interior to horsehair and the like from filaments orthreads adhere together. Such a process was advanformed of a cellulosederivative, such as, for extageous because due to the high speed ofoperample, cellulose acetate. According to these ation, economicalproduction of the desired maprocesses, a plurality of filaments orthreads was terial could be secured. When, however, this renderedplastic or swollen by means of a solvent process was carried out in anapparatus, such as or swelling agent of the material constituting thethat briefly hereinbefore described, the disadvanthread, and thefilaments or threads united into tages of such apparatus were present.the shape of. the desired final product by being A thorough study of thephenomenon involved glued together, either completely or partially. inprocesses of the type previously desired has Usually pressure wasapplied directly to the comshown that the filaments, after treatmentwith ponent elements after they had. been glued to each the swellingagent or solvent, are moistened and Otherthe swelling or plastificationof the material does Generally, in Such p edu es, t e filaments, nottake place until after a certain interval of either individually or aplurality'thereof', were time. In other words, the solvent or swelling,25 passed over into a table moistening or imagent does not immediatelyswell or render the p sn ing' vice, whereby the swelling agent orcellulose ester constituting the threads or filasolvent was pp d.Subsequently; the moisments plastic, but that this occurs after acertain tened materials were passed over a wringing (16- period of time.

vice and, when a lam was desired, between the I have found that,contrary to the usual arsurfaces of a device which applied pressure onrangement of the apparatus employed in the the band of threads, wherebythey were made to manufacture of materials to which this invenadhere.Finally, the threads, after drying, were tion relates, by positioningthe conveying or wound on a suitable collecting device. a drawingmechanism in a zone relative to the The means for conveying thefilaments through solvent-applying mechanism where the threads tapparatus was disposed ch a position are wetted or moistened with thesolvent or swellthat it drew the threads, while in a softened ing agentbut have not yet been swollen or renor swollen state, for a considerabledistance dered plastic thereby, and, after the threads or throughout theapparatus. This arrangement filaments have been swollen or renderedplastic,

40 imposed a considerable tension on the filaments onveying them underconditions which impose 40 or threads, the tension depending t great noundue tension and therefore impart no substantial stretch thereto, I canprovide a method tent upon the resistances offered by the coating, andpp tus w ich eliminates the above men flattening and/or wiping devices.Since the thread was under tension at a time when it was honeddlsadvrflntages of the pnor art and 13.1.0

duce a material without the usual degradation. softepeid and acqmred'the maxlmum Staite of It is therefore an object of this invention toplasiflclrty the filamlmts would broken if provide a method of producingartificial straws, tenslon excesswef on t j 1f tapes, ribbons, horsehairor the like, which comthe tens1on did not exceed the breaking point ofprises conveying or drawing a plurality of arti the mammal then thefilaments were Stretched ficial filaments or threads formed of acellulose 50 Also,'in a number of prior art procedu the derivativethrough a system before they have filaments were deliberately stretchedprior to the been swonen or d r d plastic and, after they collection onthe receiving device. This was sehave b nen or rendered. plastic,conveying cured by regulating the speed of the conveying of theassembled component elements under condithe thread and the speed of thereceiving device tions wherein no undue tension is applied, where- 55 bythe product; has no undue stretch imparted thereto.

Another object of this invention is to provide a method of makingmaterials of the class mentioned which comprises applying a solvent orswelling agent to a plurality of artificial threads or filaments andconveying said threads or filaments from'said applying means for adistance or interval of time insufiicient for the.

solvent or swelling agent to render the material plastic, uniting thematerials, removing the solvent or swelling agent, and winding thematerial on a suitable collection device, the last three operationsbeing carried out under substantially no undue tension on the material,whereby sub stantially no stretch is imparted thereto.

An additional object of this invention is to provide an apparatus forcarrying out the abovementioned method which comprises means to apply asolvent or swelling agent to a plurality of artificial threads orfilaments formed of a cellulose derivative, means .to draw saidfilaments or threads from the source of supply through the applyingmeans and away therefrom for a distance or time insuificient to permitthe solvent or swelling agent to act on said threads or filaments, andmeans to convey the assembled filaments or threads after they have beenswollen or rendered plastic under no undue tension, whereby nosubstantial stretch is imparted thereto.

A further object of this invention is to provide an apparatus. as setforth in the preceding paragraph wherein the drawing mechanismconstitutes a channeled roller which, in addition to effecting thefunctions already mentioned, also serves to assemble the plurality ofthreads or filaments into the shape desired.

Other objects will become apparent from the following description,appended claims and accompanying drawing wherein:

Figures, 1 and 2 designate diagrammatically several different forms ofapparatus which may be employed in accordance with the principles ofthis invention; and

Figure 3 illustrates in section a modified form of an applying means.

In accordance with the principles of the instant invention, a pluralityof artificial threads or filaments is drawn from a suitable source ofsupply and treated with a modifying agent, such as a solvent or swellingagent of the material constituting the threads or filaments. The drawingmeans is disposed in .a zone relative to said applying mechanism andconveys the filaments or threads moistened with the modifying agent fora distance or period of time which is insufficient for the modifyingagent torender the filaments or threads swollen or plastic. After thefilaments or threads have become swollen, plastic or adherent, they areconveyed under such conditionsas do not impose any undue tensionthereon, whereby the stretch is reduced to a minimum. While thefilaments and threads are thus conveyed, they are caused to unite and,after the solvent'has been substantially eliminated, the material iswound on to a suitable collection device.

The drawing or conveying mechanism may be composed of one or tworollers, one or both of which may be provided in the peripheral surfacethereof with a channel or groove having the form and shape of thedesired material. For

example, the rollers may be provided with a narrow V- or U-shapedchannel or opening or a groove of'substantially rectangular shapecorrespending to the width and/or thickness of the product to beobtained.

It is apparent that, since these rollers constitute the means forconveying the materials from the source of supply and through theapplying mechanism, they are positively driven.

These rollers, as indicated above, are disposed intermediate theapplying mechanism and winding roller. They are positioned at such adistance from the applying mechanism that, inthe course of operation,the threads or filaments conveyed from the applying mechanism are merelymoistened with the solvent or swelling agent and which has not yetrendered the materials plastic. The optimum position of the conveying ordrawing elements in any system must be chosen in accordance with thenature of the filaments, solvents or swelling agents used, and the speedof operation in such a way that the softening or gluing takes placesubstantially after the moistened materials leave this element. In suchan arrangement the moistened material does not adhere to the drawingroller.

The modifying agent, i. e'. solvent or softener, may be applied byspraying or immersing the filaments or threads in any suitable immersionapparatus or by passing them over rollers, rods, wicks or other devicesmoistened with the desired substance.

As the modifying agent, i. e. solvent or swelling agent, anysuitable'material may be used which does not immediately, uponapplication thereof to the threads or filaments, swell or soften thesame. A composition comprising 90% of acetone and 10% of ethyl alcoholhas given satisfactory results with, for example, cellulose acetatematerials.

Referring now to the drawing and particularly Figure l, the referencenumerals I, 2, 3 and 4 designate a plurality of flanged bobbins orspools containing the filaments or threads T to be united into thedesired product. If desired, a suitable braking mechanism (not shown)may be used in conjunction with these bobbins in order to govern thetension of the thread withdrawn therefrom. The artificial threads orfilaments T are withdrawn from the bobbins LA by means of the roller 5which is positively driven in any suitable manner. After withdrawing thefilaments or threads T from the spools and bobbins li, they are passedto a suitable guide 6 and thence to the solvent-applying mechanism 1.The guide 6 may serve to bundle the threads" or filaments T togetherand, together with the roller .5, are so positioned. relative to theapplying mechanism I that the threads or filaments are caused to contactwith the applying element.

In this embodiment, the applying mechanism 1 constitutes a roller 8,with or without a suitable cover, rotating in a receptacle 8 containingthe desired material. The applying element 8 may be positively driven,the direction of rotation being the same or opposite to the direction ofmovement of the materials, or it may be loosely mounted and rotated bymovement of the thread T thereover.

The roller 5 is disposed at such a distance from the applying mechanism'1 that in the course of operation the threads T contacting therewithare merely moistened with the material and have not yet been softened,plasticized or swollen. In this embodiment, the roller 5 is providedwith an annular groove 8 of the shape and size desired in the finalproduct, and thus it serves to bring the moistened threads into thedesired 'shape. I After leaving the roller 5, the assembled materialsbecome swollen and plastic and they 7 are united in the form given themby the groove 9. The solvents are then eliminatedin any suitable manneras, for example, by a suitable passage in air or through a heated tube(not shown). Finally, the material is wound on to the bobbin l which inthe form shown is frictionally driven by the element II.

The peripheral speed of the bobbin l0 and the drawing device are soregulated that the thread passing therebetween is subjected to no unduetension, with the result that the material wound on'the bobbin is notstretched to any undue deof'course, understood that in accordance withthe-principles of this invention, both of these rollers are so disposedrelative to the applying mechanism that the materials contactingtherewithare merely moistened with the solvent or swelling agent andhave not yet become swollen, plasticized or softened.

"Referring now to Figure 2, wherein a modificationutilizing' two rollersis disclosed, the reference numerals l2, l3, l4 and I5 designate spoolsof the material T and constitute a source of supply for this apparatus.From the source of supply, the threads T are withdrawn by the positivelydriven rollers I6 and I1 and caused to 'pass over a guide l8 and thenceacross the solconstituent materials, after leaving the roller H,

are caused to unite and the solvent removedas described in the precedingmodification. The material is then wound on a reel 23, the peripheralspeed of which is adjusted relative to the peripheral speed of theroller I! so that no undue tension is imparted to the thread.

The rollers l6 and I! are positively driven at the same peripheral speedor at speeds slightly different from one another.

It is to be noted that these rollers in Figure 2 are shown as one abovethe other. This is not necessary or essential for the successfulpractice of this invention. The rollers may be disposed and positionedin the same horizontal plane or otherwise as desired.

Referring now to Figure 3, there is illustrated another form ofsolvent-applying mechanism. It comprises a pervious andpreferably'absorbent material 24 supplied with the solvent by means ofcapillary action through a wick 25 suspended in a vessel 26 in which theliquid is maintained at a constant level by mechanism well known in theart. A freely mounted roller 21 in a bearing 28 serves to maintain thethreads or filaments in contact with the applying mechanism.

It is apparent that the apparatus above described may be used with anynumber of threads, depending on the product desired. Likewise, theapparatus may be employed to produce materials ing apparatus.

not as yet glued together and are, by virtue of the groove, made toassume the shape which'they wherein the threads on the exterior surfaceare only united or wherein all the threads are united.

In order to more clearly define'the nature of the invention, thefollowing specific procedures are set forth. It is to be understood thatthe process described in these examples may be carried out in any of theapparatus previously describedQand that the invention'is not restrictedto'the precise details set forth therein.

Example I.-A 300 denier, 48 filaments, 150 twist acetate thread wound ona bobbin isunwound therefrom at a linear speed of 250 m. per minute. Itis moistened by means of any coating or wetting apparatus with a mixturecom- .posed of 90% acetone and ethyl alcohol.

A conveying device composed of a roller with a narrow'and not very deepgroove is placed at a distance of from 10 cm. to 1 m. from the coat- Inthis region the filaments are are subsequently'to have in thehorsehair.

On leaving the roller, the horsehair traverses a certain distance,either in the free air or in a pipe, whereby solvent recovery isfacilitated, and

an apparatus whereby they are given an acetonecoating.

The'conveying apparatus, which may be placed at a distance of to 50 cm.fro-m the coating device, is composed of two parallel cylinders overwhich the band is wound successively, each of these cylinders or onlythe second having the groove of a practically rectangular cross-section,of 5.5 mm. width and /2 mm. depth. After these 'two rollers, the lamthus formed passes through the free air until it is practically dry andis then 'wound on a reel revolving at such a speed that there is theleast possible tension between this drum and the conveying rollers. Thisgives a very regular lam of 4 mm. thickness which has not beenstretched.

Since it is obvious that various modifications may be made in the abovedetails without departing from the nature or spirit thereof, thisinvention is not restricted thereto except as set forth in the appendedclaims.

I claim:

1. A method of making artificial horsehair, straws, tapes, bands,ribbons and the like which comprises applying a modifying agent to aplurality of artificial filaments formed of a cellulose derivative,conveying the filaments moistened with the modifying agent for a timeinsufficient to permit the modifying agent to soften or swell saidfilaments, uniting said filaments, and conveying the filaments, afterthe modifying agent acted thereon and while said filaments are in theswollen and plastic state, under such conditions that substantially nostretch is imparted thereto.

2. In a method of making artificial horsehair, straws, tapes, bands,ribbons and the like, the steps which comprise treating a plurality ofartificial filaments with a modifying agent, uniting said filamentsafter they have been swollen or rendered plastic, conveying saidfilaments after they have been swollen or rendered plastic and whilesaid filaments are in the swollen and plastic state under conditionsimposing substantially no tension thereon whereby substantially nostretch is imparted thereto, and winding the united filaments underconditions whereby substantially no stretch is imparted thereto.

3. A method of making artificial horsehair, straws, tapes, bands,ribbons and the like which comprises applying a modifying agent to aplurality cf artificial filaments formed of a cellulose derivative,conveying the filaments moistened with the modifying agent for a timeinsufiicient to permit the modifying agent'to soften or swell saidfilaments, arranging said filaments in the desired shape prior to thesoftening or swelling thereof, uniting said filaments after they havebeen swollen or rendered plastic, conveying the filaments, after themodifying agent acted thereon and while said filaments are in theswollen and 'plastic state, under such conditions that substantially nostretch is imparted thereto, and winding the united filaments underconditions whereby substantially no stretch is imparted ,thereto. ,25

4. An apparatus for making artificial horsehair, straws, tapes, bands,ribbons and the like comprising means to apply a solvent or swellingagent to a plurality of artificial filaments or threads formed of acellulose derivative, a positively driven roller having a channel in itsperipheral surface through which the treated filaments or threads pass,said roller being disposed at such a distance from the applying meansthat it will convey the treated filaments or threads before they havebecome plastic or swollen, and means cooperating with said roller toconvey the threads or filaments, after they have become plastic orswollen and while said filaments are in the swollen and plastic state,under conditions imposing no undue tension on said threads or filaments.

5. An apparatus for making artificial horsehair, straws, tapes, bands,ribbons and the like comprising means to apply a solvent or swellingagent. to a plurality of artificial filaments or threads formed of acellulose derivative, a positively driven roller having a channel in itsperipheral surface through which the treated filaments or threads pass,said roller being disposed at such a distance from the applying meansthat it will convey the treated filaments or threads before they havebecome plastic or swollen, said roller also serving to convey saidfilaments or threads from a source of supply and through the applyingmeans, and means cooperating with said roller to convey the threads orfilaments, after they have become plastic or swollen and while saidfilaments are in the swollen and plastic state, under conditionsimposing no undue tension on said threads or, filaments.

6, An apparatus for making artificial horsehair, straws, tapes, bands,ribbons and the like comprising means to apply a solvent or swellingagent to a plurality of artificial filaments or threads formed of acellulose derivative, a positively driven roller having a channel in itsperipheral surface through which the treated filaments or threads pass,said roller being disposed at such a distance from the applying meansthat it will convey the treated filaments or threads before they havebecome plastic or swollen, means cooperating with said roller to conveythe threads or filaments, after they have become plastic or swollen andwhile said filaments are in the swollen-and plastic state, underconditions imposing no undue tension on said threads or filaments, andmeans to wind the united filaments without stretching the same.

7. Anapparatus for 'making artificial horsehair, straws, tapes, bands,ribbons and the like comprising means to apply a solvent or swellingagent to a plurality of artificial filaments or threads formed of acellulose derivative, a posi tively driven roller having a channel inits peripheral surface through which the treated filaments orthreadspass, said roller being disposed at such a distance from theapplying means that it will convey the treated filaments or threadsbefore they have become plastic or swollen, said roller also serving toconvey said filaments or threads from a source of supply and through theapplying means, means cooperating with said roller to convey the threadsor filaments, after they have become plastic or swollen and while saidfilaments are in the swollen and plastic state, under conditionsimposing no undue tension on said threads or filaments, and means towind the united filaments without stretching the same.

I JEAN MARIE ALIBERT.

